Locomotive arch



June 16, 1936. .1. c. CHAPPLE LOCOMO'I IVE ARCH Filed May 29, 1951 3 Sheets-Sheet l INVENTOR BY [Zap 1Z6 June 16, 1936. J.-c. CHAPPLE 2,044,348

' LOCOMOT IVE ARCH Filed May 29, 1931 3 Sheets-Sheet 2 3.5 INVEN TOR.

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A43: ATTOR EY June 1935- J. c. CHAPPLE LocbMoTlvE ARCH Filed May 29, 1931 3 Sheets-Sheet 3 INVENTOR.

I6 [7261; [6 BY K A ATTORNEY Patented June 16, 1936 LOCOMOTIVE ARCH John C. Chapple, St. Louis, Mo. Application May 29, 1931, Serial No. 540,949

3 Claims.

This invention relates to locomotive arches, and has for its general object and purpose to provide an arch for locomotive fire boxes which is so constructed and arranged as to produce material economies in fuel consumption and maintenance of the arch, fire box structure and boiler flues.

It is common practice in this art to provide inclined water circulating tubes or such tubes in conjunction with siphons provided with means for the purpose of supporting an inclined arch or bafile wall having its rear endspaced from the fire box door sheet. The principal reason for the use of such an arch is to effect economy in fire box and flue maintenance and to effectively utilize the greatest possible percentage of heat units in the products of combustion for the evaporation of water and its conversion into steam. However, in the high powered locomotives which have come into use in recent years, such arches or bafiies as heretofore employed in the art, have not fully accomplished this purpose, since due to the increased size of the locomotive fire box and modern methods of firing, the volume of the gases of combustion is very greatly increased. Since the size of the locomotive must be restricted within certain limits, it is not possible with arches of the present design to increase the area bounded by the top of the arch, the crown sheet and the side sheets of the fire box in proportionate ratio to the increased volume of the combustion gases.

Secondly, the fire box of a modern high powered locomotive is much longer than has heretofore been the case, but it has not been found feasible to proportionately extend the length of the arch since this would result in too great a restriction of the area between the top of the arch, the crown and the side sheets. Therefore, it will be obvious that in the use of this relatively short arch, the products of combustion pass over the rear upper end thereof without scrubbing or impinging upon the door sheet or the rear portions of the side and crown sheets. Obviously therefore, these surfaces will not evaporate water, as rapidly as would be the case if the burning gases came into direct contact or impingement therewith.

Thirdly, the gases of combustion contain a certain amount of silica and other foreign matter, as well as unignited fine particles of coal so that at the high velocity at which the gases pass over the top of the arch, these unconsumed particles have an abrasive action on the crown sheet and side sheets of the fire box, resulting in quick Wear of such parts and increased maintenance cost. Further, most modern locomotives are equipped with siphons which open through the crown sheet, thereby further reducing the area above the arch and causing increased velocity and cutting action on the sheets and other parts of the fire box.

Fourthly, the majority of the high powered locomotives are stoker fired so that the fuel contains more fines than was heretofore the case. With arches of the present type, due to the high velocity of the gases, these fine particles of coal are carried through the fire box and into the tubes or fiues and hence through the stack to the atmosphere without being entirely consumed. Thus, fuel economy in the operation of the locomotive is decreased.

Also, in the use of the conventional arch construction in high powered locomotives, due to the high velocity of the gases and the restriction in area between the arch, crown and side sheets, the gases in their passage around the rear end of the arch, tend to unseat the brick constituting the upper end portion of the arch so that they either drop downwardly upon the fire bed and interfere with proper combustion of the fuel, or are thrown back over the arch against the flue sheet or into the combustion chamber portion of the fiues and thus seriously interfere with the draft. Such an occurrence, of course, also results in decreased economy in fuel con sumption.

It is the important object and purpose of my present improvements to provide an arch construction for locomotives which will eliminate the above noted defects of the conventional type of arch by changing the direction of flow of the gases and fine particles of fuel held in suspension thereby, causing the latter to be properly ignited and completely converted into burning gas before entering the fiues and also directing these ignited products of combustion against the door sheet and rear parts of the fire box.

It is another object of the invention to provide an improved form and construction of the brick for the upper portion of the arch which enables the same to be arranged in proper position between the spaced tubes or the tubes and siphons with ease and facility, and at the same time securely lock such arch bricks against a dislodgment or displacement by the action of the draft and high velocity of the gases incident thereto.

With the above and other objects in View, the invention consists in the improved locomotive arch, and in the form, construction and relative arrangement of its several parts as will be hereinafter more fully described, illustrated in the where they may close a accompanying drawings, and subsequently incorporated in the subjoined claims.

In the drawings, wherein I have disclosed several simple and practical embodiments of the essential features of my present improvements, and in which similar reference: characters designate corresponding parts throughout the several v1ews,-

Fig. l is a vertical sectional view taken on the line l-l of Fig. 2, through a locomotive fire box equipped with my improved arch;

Fig. 2 is a fragmentary sectional view taken on the line 2-2 of Fig. 1;

Fig. 3 is an enlarged detail transverse section showing the manner of interlocking the brick constituting the upper rear end of the arch in supported position between spaced siphons;

Fig. 4 is a similar view showing a modified means for retaining the baffle brick in position between the spaced siphons;

Figs. 5 and 6 are transverse sectional views through spaced arch tubes showing other modified forms of the brick for the upper portion of the arch mounted thereon;

Fig. '7 is a top plan view partly in section of the brick construction shown in Fig. 6;

Fig. 8 is a transverse sectional view through the lower end of a siphon and a circulating tube showing another form of the arch brick mounted thereon;

Fig. 9 is a side elevation of my improved deflecting interlocking arch brick;

Fig. 10 is a view similar to Fig. 6, showing a further modification for mounting the brick between the arch tubes when the latter are widely spaced apart;

Fig. 11 is a detail perspective view of a filler brick section used in the construction shown in Fig. 10;

Fig. 12 is a vertical section similar to Fig. 1, taken on the line l2-l2 of Fig. 13, and showing the arch wholly composed of my novel form of arch brick shown in Figs. 3 to 11 inclusive;

Fig. 13 is a fragmentary transverse section taken on the line. I3--l3 of Fig. 12, and

Fig. 14 is a view similar to Fig. 10, showing another form of brick which may be used in the body portion of the arch.

Referring in detail to the drawings, 5 generally indicates a locomotive fire box of more or less conventional type having the front tube or flue sheet 6 in which the rear ends of the fire tubes 1 are mounted, the rear fire door sheet 8 and the crown sheet 9. The throat sheet ID extends below and in rearwardly offset relation from the fiue sheet 6. The inclined water circulating tubes ll extending longitudinally through the fire box open at their lower ends through the throat sheet l0 and at their upper ends through the door sheet 8 adjacent to the crown sheet 9. In Figs. 1 and 2 of the drawings, I have indicated siphons l2 which are alternately arranged with respect to the tubes H and have their upper portions longitudinally elongated and opening through the crown sheet 9. The lower portions of the siphons 12 are transversely enlarged to form the bulbous or tubular portions [3 providing shoulders indicated at I4. These parts of the siphons extend in substantially parallel relation to the tubes II and forwardly from the upwardly extending parts of the siphons and open at their lower ends through the throat sheet In. The construction as above described, is standard practice in the art, and it will be understood from what follows that my improved arch may be used either in connection with such alternating tubes and siphons, or with either the tubes or the siphons alone, constituting the water circulating conduits extending through the fire box of the locomotive.

The arch or baflle wall as heretofore employed was usually composed of a plurality of tile or brick, the individual brick being either fiat with their upper and lower surfaces disposed in parallel planes or transversely curved or arched with their upper and lower surfaces substantially concentric and the concave side of the brick opposed to the fuel bed.

In Figs. 1 and 2 of the drawings, I have shown an arch or baffle wall, the greater portion of which is made up of such bricks or units I5 of standard type, the opposite ends of the bricks being formed to seat or rest upon the upper sides of the spaced arch tubes or upon one of the tubes and a shoulder M of one of the siphons 12. However, if desired, instead of using the standard type bricks IS in the body of the arch, I may use the brick l5 as shown in Fig. 14 of the drawings, in which each brick is provided at one or both side edges thereof with the lugs indicated at 15 to project under the lower tubes or other water circulating elements so that the entire arch structure will be securely locked to said elements. These bricks are in close end to end contact with the lowermost brick resting against the throat sheet spacer brick interposed between the lower end of the arch wall and the throat sheet If].

The brick constituting the upper end of the inclined arch wall which is spaced from the fire door sheet 8 are preferably of the special form and construction as illustrated in Figs. 1 and 9 of the drawings. This brick I6 is of longitudinally curved concavo-convex form having upper and lower convex and concave surfaces indicated at IT and i8 respectively to provide a brick of substantially uniform thickness, which merge into a short straight end portion l9 adapted for contact with the uppermost of the bricks IS in the arch and disposed in alignment therewith. The bricks 16 at opposite sides thereof are formed with the longitudinal extensions 20 projecting from the upper convex surface ll thereof. These projections are continua-tions of the longitudinally extending ribs or lugs 2| at each side edge of the brick. These ribs, and the lugs 20 have their lower surfaces merged together to form the seats 22 for engagement upon the upper sides of the spaced arch tubes H or on the shoulders M of the siphons I2. The longitudinally curved portion of the brick IE on one or both of its side edges below the ribs 2| is preferably formed with a concentrically curved raised portion or rib 23 constituting an interlocking projection thereon closely associated with the wall of the bulbous portion l3 of the siphon l2. It will be noted from reference to Fig. 3 of the drawings, that these side edges of the longitudinally curved portion of the brick l6 are also transversely curved as indicated at 24 so that they will extend down wardly around the part l3 of the siphon in substantially concentric relation to the wall thereof.

From the above description, it will be seen that when the arch brick it are mounted or arranged between spaced siphons as in Fig. 3, the

brick are securely locked in position against being lifted upwardly by the high velocity pressure of the gases against the concave surfaces I8 of said brick, as the gases pass upwardly around the rear end of the arch.

sides of the. supporting IE) or against suitable As shown in Fig. 4 of the drawings, instead of 7 5 providing the interlocking means formed upon opposite side edges of the curved :brick it, these side edges may extend in parallel relation to each other, and the opposed walls of the spaced siphons provided with lugs or trunnions 25 welded thereto to project over the longitudinal ribs .2 i, and thus hold the brick in position against upward movement.

As seen in Fig. 8 of the drawings, when the brick are to be mounted between a tube and a siphon, one side edge of the brick is provided a longitudinally extending groove :or channel indicated at 26 to receive one side of the tube. The opposite edge of the brick may either be provided with the integrally formed interlocking means as above referred to for cooperation with the wall of the siphon 12, or as shown in the drawings, the siphon may be provided with the holding trunnion 25 extending over the rib 2i.

In Fig. of the drawings, I have shown the brick 15 as constructed for arrangement between spaced water circulating tubes, and in which case of course, each side edge of the brick is formed with the tube receiving channel 26.

In Fig. 6 of the drawings, the brick is composed of two sections 27 and 28 respectively, the section 27 being provided with a groove 29 extending longitudinally in one edge thereof to receive the locking rib 30 formed on the corresponding mating edge of the other brick section 28.

In Figs. and 11 of the drawings, I illustrate means which permits of the mounting of the brick between spaced water circulating tubes or siphons, when the latter are relatively widely spaced apart. In this case a filler brick section 3! is used and interposed between the two brick sections 32 and 33 respectively. One side of the filler section 31 is provided with the projecting rib 3 while the other side has a groove 35 therein. The rib 34 interlocks in the groove 38 on the brick section 32, while the groove 35 receives the interlocking rib 3? formed on the brick section 33. In this manner, the two brick sections may be securely looked together in properly supported position upon the widely spaced tubes or other water conductors.

From reference to Fig. l of the drawings, it will be readily seen that by means of an arch of the construction described, the gases and products of combustion rising from the fuel bed, strike the under side of the arch and move upwardly by reason of the draft along the under side thereof. When the gases strike the concave curved surfaces is of the brick l6 at the upper end of the arch, their course is deflected downwardly towards the fuel bed, and against the fire door sheet 8. Therefore, any fine particles of coal or other matter which has not been ignited will be thrown into the zone of intense heat so that the ignition and conversion into gas of such particles is assured. The large volume of gas may hence, pass freely upwardly along the fire door sheet 8 and into contact with the crown sheet 9 so that the greatest possible percentage of the heat units in the consumed fuel will be utilized in the evaporation of the water in contact with the side sheets, the door sheet 8 and the crown sheet 9 of the firebox. The products of combustion, as they are drawn forwardly over the upper end of the arch being almost wholly in the form of burning gas, although passing at high velocity into the fire tubes 6, will also by reason of their impingement upon the walls of the siphons l2, bring about further evaporation of the water passing upwardly through these siphons and through the 3 crown sheet .9. In this manner, I obtain maximum economy in consumption of fuel with low maintenance cost due to elimination of wear upon the parts of the firebox .structure by contact of :unconsumedfuel products therewith. 5

In Figs. .12 and 13 of the drawings, I have shown arch entirely .made up of my new type of deflecting brick :or tile :as above described, and in which the longitudinally curved bricks are arranged :upon the water circulating elements ex- 0 tending through the fire box in pairs with the bricks in each ,pair disposed in relatively reversed positions so that their lower concave faces form a substantially continuous arc. Thus, the succession of pairs of bricks l6 form on the under side of the arch, a series of pockets or chambers 38. These pockets repeatedly change the course or direction of the gases in their upward flow through the fire box, and in addition to the concentrated heating effect upon the water circulating elements which thus results, the gases are more thoroughly mixed, and any small particles of fuel unignited or only partially consumed are returned to the fuel bed, or their progress through the .fire box is so delayed before passage above the arch that complete ignition or combustion thereof is assured. The gases upon leaving the uppermost chamber 38 of the arch are deflected and directed downwardly and rearwardly against the fire door and side sheets of the fire box, as in the arrangement previously described.

From the foregoing description considered in connection with the accompanying drawings, the construction and several advantages of my improved locomotive arch will be clearly and fully understood. It will be seen that my new arch brick i5 is of relatively simple form, and may be easily molded or shaped from refractory material. Also, these brick can be easily and quickly applied in position at the upper end of the arch and when properly arranged are securely locked against liability of being dislodged and falling upon the fuel bed or moved rearwardly by the draft against the lower fire tube 1 wherewould be closed and thus obstruct the free circulation of the products of combustion through the fines. I have herein shown and described several desirable embodiments of the essential features of my present invention, but it will be understood that these are merely suggestive, and my improvements might also be in corporated in various other alternative structural forms. Accordingly, the privilege is reserved of resorting to all such legitimate changes therein as may be fairly embodied within the spirit and scope of the invention as claimed.

I claim:

1. In a locomotive fire-box which includes transversely spaced water-circulating elements extending longitudinally and rearwardly through 60 the fire-box from the thrust-sheet thereof, arch walls supported upon and between adjacent water-circulating elements and comprising adjoining refractory fire bricks having curving top walls curving towards the adjacent elements at 65 the opposite ends of the brick, supporting walls connected to and projecting from the opposite ends of-the bricks and shaped to form overhanging shoulders the underfaces of which rest upon said elements, side walls connected to and ex- 70 tending downwardly from the top walls between said elements and terminating substantially below the same, said bricks below the top walls thereof being without end walls and the side walls thereof affording below the top walls through chan- 75 nels extending between the adjacent elements and in which the high velocity gases from the fire-box are received and distributed directly against said elements.

2. In a top arch for a locomotive fire-box having refractory bricks and longitudinally extending water-circulating elements supporting said bricks and extending upwardly between the thrust-sheet and rear fire door sheet of the firebox, said bricks comprising bodies disposed in abutting side to side relation and having at their opposite ends top extensions extending beyond the bodies and resting upon said elements, said bodies having underneath channels opening through the ends of the brick below said topextensions and adjacent said elements, the sides of the bricks being disposed between said elements and at least one side of each brick extending downwardly therebetween and terminating substantially below the underneath surface of said elements, said downwardly extending sides of the bricks between said elements traversing and interrupting the flow of high velocity gases proceeding longitudinally of the arch toward. the fire door sheet and said through channels providing for the distribution of the interrupted gases directly against said elements.

3. In a locomotive fire-box arch which includes spaced apart water-circulating elements extending longitudinally through the fire-box and upwardly from the thrust-sheet thereof, an arch wall supported upon said elements comprising adjoining refractory fire bricks and each having a top wall and side walls, the latter disposed between said elements and extending substantially below the same and spaced apart to form under the top wall a through channel open at the bottom and at the ends of the brick, supporting walls on the bricks connected to and projecting from the opposite ends of the top walls thereof and shaped to form overhanging shoulders which rest at their under-surfaces upon said elements and position the bricks with the open ends of their through channels directly facing said elements, such arch of adjoining bricks providing between the bricks themselves abutting side walls and providing between said elements through channels in which the high velocity gases from the fire-box are received and distributed directly against said elements.

JOHN C. CHAPPLE. 

